Piston and cylinder apparatus for dampening of a spring-loaded sliding door

Abstract

In some examples, a piston and cylinder apparatus may include a male piston mountable to a slidable door of an instrument and insertable into a female receiver mountable to an instrument enclosure of the instrument to controllably stop movement of the door.

Description

Docket No. 20250003-02PISTON AND CYLINDER APPARATUS FOR DAMPENING OF A SPRING-LOADED SLIDING DOORCROSS-REFERENCE TO RELATED APPLICATION(S)

[0001] This application claims priority to U.S. Provisional Application Serial No.63 / 777,230, filed March 25, 2025, titled “PISTON AND CYLINDER APPARATUS FOR DAMPENING OF A SPRING-LOADED SLIDING DOOR”, the disclosure of which is incorporated by reference in its entirety.BACKGROUND

[0002] An instrument, such as a trace explosives detector or another such device, may include a sliding door that is opened to access or place a sample in the instrument, and closed during sample analysis or when the instrument is not in use. In some cases, the sliding door may be manually closed to seal the sample placed in the instrument during analysis of the sample. The sliding door may be spring-loaded such that once a latch holding the sliding door closed is released, the sliding door automatically slides to a fully open position.1Docket No. 20250003-02 BRIEF DESCRIPTION OF DRAWINGS

[0003] Features of the present disclosure are illustrated by way of example and not limited in the following figure(s), in which like numerals indicate like elements, in which:

[0004] Figure 1 illustrates a piston and cylinder apparatus for dampening of a spring-loaded sliding door (hereinafter “piston and cylinder apparatus”), in accordance with an example of the present disclosure;

[0005] Figure 2 illustrates further details of components of the piston and cylinder apparatus of Figure 1, in accordance with an example of the present disclosure;

[0006] Figures 3-5 illustrate a sliding door and piston / cylinder interaction to illustrate operation of the piston and cylinder apparatus of Figure 1, in accordance with an example of the present disclosure;

[0007] Figure 6 illustrates further dimensional details of the piston and cylinder apparatus of Figure 1, in accordance with an example of the present disclosure;

[0008] Figure 7 illustrates a configurable orifice usable with the piston and cylinder apparatus of Figure 1, in accordance with an example of the present disclosure; and

[0009] Figure 8 illustrates an example of an instrument that may utilize the piston and cylinder apparatus of Figure 1, in accordance with an example of the present disclosure.2Docket No. 20250003-02 DETAILED DESCRIPTION

[0010] For simplicity and illustrative purposes, the present disclosure is described by referring mainly to examples. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure. It will be readily apparent however, that the present disclosure may be practiced without limitation to these specific details. In other instances, some methods and structures have not been described in detail so as not to unnecessarily obscure the present disclosure.

[0011] Throughout the present disclosure, the terms "a" and "an" are intended to denote at least one of a particular element. As used herein, the term "includes" means includes but not limited to, the term "including" means including but not limited to. The term "based on" means based at least in part on.

[0012] A piston and cylinder apparatus for dampening of a spring-loaded sliding door (hereinafter “piston and cylinder apparatus”) is disclosed herein. The piston and cylinder apparatus may include a floating female air cylinder (e.g., “female receiver” as disclosed herein) with an internal O-ring. The female receiver may be mounted to an instrument enclosure of an instrument, while a male piston may be mounted to a sliding door. Alternatively, the female receiver may be mounted to the sliding door, while a male piston may be mounted to the instrument enclosure of the instrument. When the sliding door is released (e.g., pulled open by its spring), the male piston may engage the female receiver with the O-ring sealing an air pocket between them, while air is released through an orifice in the male piston to controllably stop movement of the door.

[0013] With respect to instruments, such as a trace explosives detector or another such device, as disclosed herein, the instrument may include a sliding door that is openedDocket No. 20250003-02 to access or place a sample in the instrument, and dosed during sample analysis or when the instrument is not in use. In some cases, the sliding door may be manually closed to seal the sample placed in the instrument during analysis of the sample. The sliding door may be spring-loaded such that once a latch holding the sliding door closed is released, the sliding door automatically slides to a fully open position. Without a damper, the sliding door may abruptly impact a hard stop of the instrument enclosure, which can generate a loud noise and vibrations that may shift the entire instrument. In this regard, it is technically challenging to control stopping of the sliding door that needs to be rapidly slid opened, without the sliding door impacting the instrument enclosure and / or generating noise and vibrations that may interfere with instrument operation.

[0014] In order to address at least the aforementioned technical challenges, the piston and cylinder apparatus disclosed herein effectively dampens the potential impact of the fast-moving sliding door against the instrument enclosure. The piston and cylinder apparatus also provides adaptive dampening. In this regard, the piston and cylinder apparatus dampens varying potential impact forces due to different speeds of the sliding door, while still allowing the door to fully open without becoming stuck at a midway point. The piston and cylinder apparatus eliminates any loud noises and significantly reduces vibrations caused by the door’s impact against the instrument enclosure, for example, by preventing impact of the door against the instrument enclosure, or otherwise controlling a velocity of impact of the door against the instrument enclosure. Additionally, the piston and cylinder apparatus creates a repeatable and smooth feel during the automatic opening or release of the sliding door, allowing the sliding door to travel and stop smoothly, as opposed to abruptly impacting the instrument enclosure and vibrating theDocket No. 20250003-02 instrument.

[0015] According to examples disclosed herein, the piston and cylinder apparatus provides adaptive dampening through pneumatic energy absorption, which is capable of absorbing different impact forces and speeds, while also allowing for the full opening of the door.

[0016] According to examples of the piston and cylinder apparatus disclosed herein, the female receiver may include a “floating” design that allows it to work under relatively large misalignments of the sliding door mechanisms.

[0017] According to examples of the piston and cylinder apparatus disclosed herein, the female receiver may include a “floating” design that allows it to work under relatively large misalignments of the sliding door mechanisms.

[0018] According to examples of the piston and cylinder apparatus disclosed herein, the components of the piston and cylinder apparatus may be utilized with instruments with ‘unit- to-unit’ variations without the need for manual adjustment.

[0019] According to examples disclosed herein, the piston and cylinder apparatus ensures that the sliding door fully opens over continuous cycles, without becoming stuck midway, even if the spring force reduces over time as the pneumatic dampening is adaptive to the force applied.

[0020] According to examples disclosed herein, the piston and cylinder apparatus provides for extended use throughout the lifecycle of the instrument.

[0021] According to examples disclosed herein, a piston and cylinder apparatus may include a male piston mountable to a slidable door of an instrument and insertable into aDocket No. 20250003-02 female receiver mountable to an instrument enclosure of the instrument to controllably stop movement of the door.

[0022] According to examples of the piston and cylinder apparatus disclosed herein, the instrument may include a trace explosives detector

[0023] According to examples of the piston and cylinder apparatus disclosed herein, the male piston may include an orifice that is configured to release air disposed in the female receiver through the male piston to controllably stop movement of the door.

[0024] According to examples disclosed herein, the piston and cylinder apparatus may further include a fastener including an orifice and removably attachable to the male piston, where the orifice is configured to release air disposed in the female receiver through the male piston to controllably stop movement of the door. The orifice may be sized to control a rate of release of air disposed in the female receiver through the male piston.

[0025] According to examples of the piston and cylinder apparatus disclosed herein, the female receiver may include a cylindrical configuration to receive a complementary cylindrically shaped male piston.

[0026] According to examples of the piston and cylinder apparatus disclosed herein, the female receiver may include a non-cylindrical configuration to receive a complementary non-cylindrically shaped male piston.

[0027] According to examples of the piston and cylinder apparatus disclosed herein, the male piston may be separated from the female receiver by an air gap when the male piston is not inserted into the female receiver. For example, when the male piston isDocket No. 20250003-02 mounted to the door and the female receiver is mounted to the instrument enclosure, the male piston may be separated from the female receiver by an air gap. In this manner, the male piston and the female receiver can be disposed on two separate components and engage each other during opening / closing movement of the components, but otherwise remain apart when the components are separated.

[0028] According to examples disclosed herein, the piston and cylinder apparatus may further include at least one grommet to attach the female receiver to the instrument to allow for transverse movement of the female receiver during insertion of the male piston. In one example, the at least one grommet may include two grommets with each grommet being disposed on opposite sides of a central axis of the female receiver.

[0029] According to examples disclosed herein, an instrument may include an instrument enclosure, and a door slidably mounted to the instrument enclosure. A male piston may be mounted to the door of the instrument and insertable into a female receiver mounted to the instrument enclosure to controllably stop movement of the door.

[0030] According to examples of the instrument disclosed herein, the male piston may include an orifice that is configured to release air disposed in the female receiver through the male piston to controllably stop movement of the door.

[0031] According to examples disclosed herein, the instrument may further include a fastener including an orifice and removably attached to the male piston, where the orifice is configured to release air disposed in the female receiver through the male piston to controllably stop movement of the door. The orifice may be sized to control a rate of release of air disposed in the female receiver through the male piston.Docket No. 20250003-02

[0032] According to examples disclosed herein, the instrument may further include at least one grommet to attach the female receiver to the instrument to allow for transverse movement of the female receiver during insertion of the male piston. In one example, the at least one grommet may include two grommets with each grommet being disposed on opposite sides of a central axis of the female receiver.

[0033] According to examples disclosed herein, a piston and cylinder apparatus may include a male piston mountable to a first part of an instrument that is movable relative to a second part of the instrument, where the male piston may be insertable into a female receiver mountable to the second part of the instrument to controllably stop movement of the first part relative to the second part.

[0034] According to examples of the piston and cylinder apparatus disclosed herein, the male piston may include an orifice that is configured to release air disposed in the female receiver through the male piston to controllably stop movement of the first part relative to the second part.

[0035] According to examples disclosed herein, the piston and cylinder apparatus may further include a fastener including an orifice and removably attachable to the male piston, where the orifice may be configured to release air disposed in the female receiver through the male piston to controllably stop movement of the first part relative to the second part.

[0036] According to examples disclosed herein, the piston and cylinder apparatus may further include at least one grommet to attach the female receiver to the second part to allow for transverse movement of the female receiver during insertion of the male piston. In one example, the at least one grommet may include two grommets with eachDocket No. 20250003-02 grommet being disposed on opposite sides of a central axis of the female receiver.

[0037] Figure 1 illustrates a piston and cylinder apparatus for dampening of a spring-loaded sliding door (hereinafter “piston and cylinder apparatus 100”), in accordance with an example of the present disclosure.

[0038] Referring to Figure 1, the piston and cylinder apparatus 100 may include a male piston 102 mountable to a slidable door 104 of an instrument (e.g., instrument 800 of Figure 8) by a mounting bracket 106 and insertable into a female receiver 108 mountable to an instrument enclosure (e.g., instrument enclosure 802 of Figure 8) of the instrument 800 to controllably stop movement of the door 104. The male piston 102 may include an orifice 110 that is configured to release air disposed in the female receiver 108 through the male piston 102 to controllably stop movement of the door 104. In the example of Figure 1, the door 104 may slide on shafts 112-1 and 112-2 that are mounted to the instrument 800.

[0039] In one example, as shown in Figure 1, the female receiver 108 may include a cylindrical configuration to receive a complementary cylindrically shaped male piston 102. Alternatively, the female receiver may include a non-cylindrical configuration (e.g., oval, rectangular, etc.) to receive a complementary non-cylindrically shaped male piston.

[0040] The piston and cylinder apparatus 100 may further include at least one grommet 114 to attach the female receiver 108 to the instrument 800 to allow for transverse movement of the female receiver 108 during insertion of the male piston 102. In one example, the at least one grommet 114 may include two grommets with each grommet being disposed on opposite sides of a central axis 116 of the female receiverDocket No. 20250003-02

[0041] Figure 2 illustrates further details of components of the piston and cylinder apparatus 100, in accordance with an example of the present disclosure.

[0042] Referring to Figures 1 and 2, and particularly Figure 2, the female receiver 108 may include an internal O-ring 200. When the sliding door 104 is released (e.g., pulled open by its spring), the male piston 102 may engage the female receiver 108 with the O-ring 200 sealing an air pocket between them, while air is released through the orifice 110 in the male piston 102 to controllably stop movement of the door 104. The female receiver 108 may be mounted to the instrument 800 by means of the grommets, with each grommet 114 being disposed between the female receiver 108 and the instrument 800, and mounted by means of a screw 202 and a collar 204.

[0043] The male piston 102 and the female receiver 108 may be formed of polyoxymethylene (POM), or another such material, for its low friction and high wear resistance. The O-ring 200 and the grommet 114 may be formed of 50 Shore A NBR material (e.g., Nitrile Butadiene Rubber (NBR) material with a hardness measurement of 50 on the Shore A scale), or other such materials.

[0044] The hardness of the O-ring material allows smooth engagement of the male piston 102 with the female receiver 108, without the male piston 102 and the female receiver 108 becoming stuck. Further, the grommet 114 allows the female receiver 108 to “float” (e.g., move transversely as needed) without having hard-to-hard surface contact.

[0045] Figures 3-5 illustrate a sliding door and piston / cylinder (e.g., female receiver) interaction to illustrate operation of the piston and cylinder apparatus 100, in accordance with an example of the present disclosure.Docket No. 20250003-02

[0046] Referring to Figure 3, at 300 (e.g., Position-0), the door 104 may be fully closed. A sectional view of the female receiver 108 is shown at 302. At Position-0, the male piston 102 may be disposed at a distance away from the female receiver 108. Further, at Position-0, the door 104 may be latched shut (e.g., by a latch mechanism (not shown)).

[0047] Referring to Figure 4, at 400 (e.g., Position-1), the door 104 may be opened, for example, by releasing the latch mechanism (not shown) and automatically travel from Position-0 to Position-1 by means of spring assist or another type of assist (e.g., a torsion spring mechanism 804 as shown in Figure 8). A sectional view of the female receiver 108 with the male piston 102 partially inserted therein is shown at 402. At Position-1, the male piston 102 enters the female receiver 108, with the entry being guided by the O-ring 200. A lead-in chamfer 404 of the female receiver 108 may facilitate guidance of the male piston 102 into the female receiver 108 so that the female receiver 108 conforms and aligns to the angle of entry of the male piston 102. The grommets allow for transverse movement of the female receiver 108 during insertion of the male piston 102, to thus align the male piston 102 within the female receiver 108. The O-ring 200 starts to seal the male piston 102 and the female receiver 108, forming an air pocket between them, which gets pressurized. At this stage, air within the female receiver 108 may be released through the orifice 110 to begin to controllably stop sliding movement of the door 104.

[0048] Referring to Figure 5, at 500 (e.g., Position-2), the door 104 may be fully opened after continuing to automatically travel from Position-1 to Position-2 by means of spring assist or another type of assist. At Position-2, the male piston 102 fully enters the female receiver 108, with the entry being guided by the O-ring 200. In this regard, airDocket No. 20250003-02 within the female receiver 108 continues to be released through the orifice 110 to fully controllably stop movement of the door 104.

[0049] With respect to operations of the apparatus 100 described herein with reference to Figures 3-5, when a small force is applied on the sliding door 104, the pressure build-up in the female receiver 108 will be lesser as well. This will counter the sliding door force, until it reaches terminal velocity, where the door 104 will travel at a constant speed until it reaches hard stop (e.g., Position 2).

[0050] However, when a large force is applied to open the sliding door 104, the pressure build-up in the female receiver 108 will be greater. This creates greater resistance to the sliding door force and provides proper damping to the door impact.

[0051] Hence, the apparatus 100 creates an adaptive dampening effect, without the need of any manual adjustment. In this regard, the apparatus 100 accounts for varying forces and speeds of the sliding door 104, even for stroke-to-stroke force variations.

[0052] The kinetic energy of the sliding door 104 may be converted to pressure build¬ up in the female receiver 108. This may be expressed by the following equations:^kinetic ~~ 1.. 1 2 - -mvF = (? M. ~~ ) - PM Equation-1F1 -. ---mv / = F2L2. ------. FiL.. Eq2£ A-. Equation-2Docket No. 20250003-02Assume F, = F = F(>= FEquation-31, zU,\ / V; X Q..l / V; \ Sub Eq3 mtoEql. ~~mvp ~ ~ - ■1,, Fz “ L, "z '”1'1" t: TA ~ I ~ mv\ - - t...... Eq4Equation-4 For Equation-1 to Equation-4, the variables may be defined as follows:A — change in kinetic energy of the sliding door~ work done on pressure build up in the female cylinderm ™ mass o f doorst’j ™ initial velocity o f doorv2= final velocity of doorp - pressure in cylindert— initial pressure in cylinderP2- final pressure in cylinderPa™ pressure released through orificeDocket No. 20250003-02~ volume of cylinder— initial volume of cylinderVj ™ final volume of cylinderVo— air volume of escaped through orificevl = cross sectional area of cylinderAj?™ cross sectional area of orificeQ(>~ air flow rate at orificeL = distance between male piston and f emale cylinder}— initial distance between male piston and female cylinderl2final distance between male piston and female cylindert = time required for door to stopF ™ door impact forceFj — initial force on cylinder— f inal force on cylinderFo— final force on orifice& L - distance required for door to stop

[0053] Figure 6 illustrates further dimensional details of the piston and cylinder apparatus 100, in accordance with an example of the present disclosure.

[0054] Referring to Figure 6, based on the derived Equation-4 and the variables specified above, a larger door mass (m), a faster door speed (v1) and a larger orifice size (Ao), where “o” represents the orifice, will utilize a longer distance for the door to stop (AL). In this regard, a size of the orifice 110 may be adjusted to create different effects ofDocket No. 20250003-02 door stopping time and distance.

[0055] Figure 7 illustrates a configurable orifice usable with the piston and cylinder apparatus 100, in accordance with an example of the present disclosure.

[0056] Referring to Figure 7, the piston and cylinder apparatus 100 may further include a fastener 700 including an orifice 702 and removably attachable to the male piston 102. The orifice 702 may be configured to release air disposed in the female receiver 108 through the male piston 102 to controllably stop movement of the door 104. The orifice 702 may be sized to control a rate of release of air disposed in the female receiver 108 through the male piston 102. Thus, the fastener 700 may be replaced as needed with a fastener that includes a differently sized orifice to control a rate of release of air disposed in the female receiver 108 through the male piston 102. The orifice 702 may itself be made adjustable, for example, by a tube or another insert that may be placed within the orifice 702 of the fastener 700 to increase or decrease an opening area of the orifice 702.

[0057] Figure 8 illustrates an example of an instrument that may utilize the piston and cylinder apparatus 100, in accordance with an example of the present disclosure.

[0058] Referring to Figure 8, the door 104 at a closed position is shown, for example, at 804 and 808, respectively, in a front view and a rear view of the instrument 800, and at an open position is shown, for example, at 806 and 810, respectively, in a front view and a rear view of the instrument 800. The door 104 may be opened, for example, by releasing a latch mechanism (not shown) and automatically open by means of spring assist or another type of assist (e.g., the torsion spring mechanism 804). Further, as disclosed herein, opening of the door 104 may be dampened by the piston and cylinderDocket No. 20250003-02 apparatus 100 until the door 104 is fully open.

[0059] What has been described and illustrated herein is an example along with some of its variations. The terms, descriptions and figures used herein are set forth by way of illustration only and are not meant as limitations. Many variations are possible within the spirit and scope of the subject matter, which is intended to be defined by the following claims -and their equivalents -in which all terms are meant in their broadest reasonable sense unless otherwise indicated.

Claims

Docket No. 20250003-02 What is claimed is:

1. An apparatus comprising:a male piston mountable to a slidable door of an instrument and insertable into a female receiver mountable to an instrument enclosure of the instrument to controllably stop movement of the door.

2. The apparatus according to claim 1, wherein the instrument includes a trace explosives detector.

3. The apparatus according to claim 1, wherein the male piston includes an orifice that is configured to release air disposed in the female receiver through the male piston to controllably stop movement of the door.

4. The apparatus according to claim 1, further comprising:a fastener including an orifice and removably attachable to the male piston, wherein the orifice is configured to release air disposed in the female receiver through the male piston to controllably stop movement of the door.

5. The apparatus according to claim 4, wherein the orifice is sized to control a rate of release of air disposed in the female receiver through the male piston.Docket No. 20250003-026. The apparatus according to claim 1,wherein the female receiver includes a cylindrical configuration to receive a cylindrically shaped male piston, orwherein the female receiver includes a non-cylindrical configuration to receive a non-cylindrically shaped male piston.

7. The apparatus according to claim 1, wherein the male piston is separated from the female receiver by an air gap when the male piston is not inserted into the female receiver.

8. The apparatus according to claim 1, further comprising:at least one grommet to attach the female receiver to the instrument to allow for transverse movement of the female receiver during insertion of the male piston.

9. The apparatus according to claim 8, wherein the at least one grommet includes two grommets with each grommet being disposed on opposite sides of a central axis of the female receiver.

10. An instrument comprising:an instrument enclosure;Docket No. 20250003-02 a door slidably mounted to the instrument enclosure; anda male piston mounted to the door of the instrument and insertable into a female receiver mounted to the instrument enclosure to controllably stop movement of the door.

11. The instrument according to claim 10, wherein the male piston includes an orifice that is configured to release air disposed in the female receiver through the male piston to controllably stop movement of the door.

12. The instrument according to claim 10, further comprising:a fastener including an orifice and removably attached to the male piston, wherein the orifice is configured to release air disposed in the female receiver through the male piston to controllably stop movement of the door.

13. The instrument according to claim 12, wherein the orifice is sized to control a rate of release of air disposed in the female receiver through the male piston.

14. The instrument according to claim 10, further comprising:at least one grommet to attach the female receiver to the instrument to allow for transverse movement of the female receiver during insertion of the male piston.

15. The instrument according to claim 14, wherein the at least one grommet includesDocket No. 20250003-02 two grommets with each grommet being disposed on opposite sides of a central axis of the female receiver.

16. An apparatus comprising:a male piston mountable to a first part of an instrument that is movable relative to a second part of the instrument, wherein the male piston is insertable into a female receiver mountable to the second part of the instrument to controllably stop movement of the first part relative to the second part.

17. The apparatus according to claim 16, wherein the male piston includes an orifice that is configured to release air disposed in the female receiver through the male piston to controllably stop movement of the first part relative to the second part.

18. The apparatus according to claim 16, further comprising:a fastener including an orifice and removably attachable to the male piston, wherein the orifice is configured to release air disposed in the female receiver through the male piston to controllably stop movement of the first part relative to the second part.

19. The apparatus according to claim 16, further comprising:at least one grommet to attach the female receiver to the second part to allow for transverse movement of the female receiver during insertion of the male piston.Docket No. 20250003-0220. The apparatus according to claim 19, wherein the at least one grommet includes two grommets with each grommet being disposed on opposite sides of a central axis of the female receiver.

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